Site-directed analysis of the functional domains in the Factor Xa inhibitor Tick Anticoagulant Peptide: identification of two distinct regions that constitute the enzyme recognition sites - Dunwiddie, CT; Neeper, MP; Nutt, EM; Waxman, L; Smith, DE; Hofmann, KJ; Lumma, PK; Garsky, VM; Vlasuk, GP (Biochemistry, 1992)